California lawmakers yesterday called for the regulation of marijuana farms to protect stream flows and help fish species like coho salmon and steelhead, which face possible extinction as the state's drought rages on.

In an informational hearing of the California State Senate Joint Committee of Fisheries and Aquaculture, Chairman Mike McGuire (D) of Healdsburg argued that a contingent of pot farmers in the state have disregarded the environment in favor of personal profit.

"Marijuana is literally sucking rivers dry," McGuire said.

The impacts of California's drought on key fisheries have been of increasing concern for wildlife agencies across the state, which have worked for decades to restore fish populations to their historic levels. In 2014, warm water conditions contributed to a 95 percent mortality of winter run brood salmon in the Sacramento River system. This year, with cold water stocks in the Shasta Reservoir—located in Northern California about 9 miles northwest of Redding—at record low levels, Chuck Bonham, director of the California Department of Fish and Wildlife (CDFW), said the state faces another loss of brood stock this winter.

Across the state, there are an estimated 50,000 small pot farms. In the last decade, under the auspices of Proposition 215, which legalized marijuana for medical use, there has been a steady increase in the amount of cannabis cultivation in Shasta, Tehama and Humboldt counties, according to DeWayne Little, a lieutenant with CDFW's Watershed Enforcement Team.

A study by CDFW and published in the journal PLOS ONE in March, found that in four watersheds that are home to both coho salmon and large numbers of marijuana farms—which use about 22 liters of water per day, per plant—the pot cultivation drained much of the river's water (E&ENews PM, March 25)

Illegal water diversions, as well as increased sedimentation and pesticide use, are the main environmental impacts from marijuana grow operations, according to Little. The problem is pronounced along California's North Coast and especially in Mendocino, Humboldt and Trinity counties—or what's known as the Emerald Triangle, the largest cannabis-producing region in the world. In Humboldt County alone, the CDFW estimates there are about 4,000 grow operations.

Officials testify to 'alarming' water diversions
Without regulation, grow operations have moved in and are operating without best management practices, affecting natural resources as a result, Little said.

About nine months ago, California officials created a multiagency pilot program involving state and local agencies. The program is tasked with developing a regulatory program for cannabis activities, conducting targeted enforcement and engaging in education and outreach with local communities.

The seven-member team has visited nearly 100 grow sites and has issued one fine totaling $300,000, five cleanup and abatement orders, and a number of minor violation notices, said Thomas Howard, executive director of the California State Water Resources Control Board.

That rate of inspection has been considered a success, Howard said, but that level of enforcement is barely scratching the surface considering how many farms are suspected to be unregulated in the state.

As of last month, Little said several major rivers are at or near historic lows, including the Van Duzen River, the Eel River, Redwood Creek and Trinity Creek, and his team hypothesizes that these reductions in water are being caused by illegal diversions by grow operations, new and poorly constructed ponds, and improper road construction.

"We have grows that are larger than ever," Little testified during the hearing, which was also webcast live. "Streams are being diverted at an alarming rate."

Little cited a recent example of a portion of stream his team encountered near Fish Lake in Humboldt County in which pot farmers were using PVC pipe, Dixie cups, funnels and even 2-liter Pepsi bottles to divert water for 5,000 plants.

"There literally wasn't a drop of water left after that diversion," he added.

Fears of what legalized marijuana will bring
Humboldt County Sheriff Tom Allman shared similar stories. A native of Humboldt, Allman recalled the early 1970s, when "hippies" began to move to the area, bringing with them marijuana grows. But, he said, those were responsible operations. What he sees today is something entirely different.

"The old hippies are not the problem," he said. "The problem is the 20-year-olds with a sore shoulder who want to make $1 million in a year."

As a result, Allman said, the local fishing and tourism economy is being damaged. If recreational marijuana is legalized by voter referendum in 2016, he said, he fears the continued detrimental effect of unregulated pot farms on those who live on the North Coast.

Some in the marijuana industry echoed the calls of law enforcement, wildlife officials and politicians who spoke during the hearing.

The California marijuana industry is estimated to produce about 20 million pounds of pot annually, and Allen said the small farmers he represents would welcome regulations and rules that treat them accordingly.

As the drought and further impacts from climate change continue, McGuire stressed that lack of action is jeopardizing entire species in California's watersheds.

"This needs to be the year that legislation is finally passed to bring forward those rules and regulations," McGuire said. "I know some people may still be uncomfortable with medical marijuana, but how many years are we going to allow this to happen?"

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